Check this table for the answer:
http://www.remingtonsociety.com/rsa/questions/barrelcodes
See related link.
Made by the Remigton Firearms Company.
Contact Remington Customer Service thru their website.
The W ahead of the serial number indicates that your Remington 870 wingmaster was made in 1972.
Check this table for the answer: http://www.remingtonsociety.com/rsa/questions/barrelcodes
They are all still made in Illion, New York, I believe.
Do a search on barrel codes, I believe that will give you an answer
Remington Society barrel code lookup: http://remingtonsociety.com/rsa/questions/barrelcodes
$2
Check this table for the answer: http://www.remingtonsociety.com/rsa/questions/barrelcodes
Check the date code stamp on the left side of the barrel you can get the details and look it up on the Remington Society of America under the manufactured date link.
All Remington model 870 shotguns were made in the Unites states.The Remington plant was located in Ilion,New York.